1. Field
Example embodiments generally relate to a cleaning device used in an image forming apparatus such as a copying machine and a printer, and an image forming apparatus using the same.
2. Description of the Related Art
A related-art image forming apparatus, such as a copying machine, a facsimile machine, a printer, or a multifunction printer having two or more of copying, printing, scanning, and facsimile functions, forms a toner image on a recording medium (e.g., a sheet) according to image data by an electrophotographic method. In such a method, for example, a charger charges a surface of an image carrier (e.g., a photoconductor). An optical device emits a light beam onto the charged surface of the photoconductor to form an electrostatic latent image on the photoconductor according to image data. The electrostatic latent image is developed with a developer (e.g., a toner) to form a toner image on the photoconductor. A transfer device transfers the toner image formed on the photoconductor onto a sheet. A fixing device applies heat and pressure to the sheet bearing the toner image to fix the toner image on the sheet. The sheet bearing the fixed toner image is then output onto an outside of the image forming apparatus.
The related-art image forming apparatus further includes a cleaning device, for example, for cleaning a surface of a cleaning target such as a fixing member. Such a cleaning device cleans the surface of the cleaning target by contacting a cleaning web with the surface of the cleaning target. For example, the cleaning device includes a supply roller for supplying an unused portion of a cleaning web wound thereon, and a rewinding roller for rewinding a used portion of the cleaning web supplied from the supply roller. The cleaning web stretched between the supply roller and the rewinding roller is in contact with the surface of the cleaning target.
In the cleaning device described above, the surface of the cleaning target in contact with the cleaning web moves relative to the movement of the cleaning web. Therefore, the cleaning web cleans the surface of the cleaning target by contacting the surface of the cleaning target. When an amount of dirt collected by the cleaning web reaches a predetermined or given level, the rewinding roller is rotated so that a new portion of the cleaning web is supplied and brought into contact with the surface of the cleaning target.
As a method for determining a timing of rewinding a cleaning web, a technique of measuring a cleaning time in which the cleaning web is in contact with a cleaning target to clean the cleaning target is proposed. According to the above-described method, the cleaning web is rewound when the measured cleaning time exceeds a setting time set in advance.
However, in the above-described cleaning device, there is a problem that, the number of times in which the cleaning operation is performed varies depending on moving speed of the cleaning target. For example, when the moving speed of the cleaning target is lower, a longer time is required for performing a single cleaning operation, so that the cleaning operation is performed a fewer number of times within the setting time. As a result, the cleaning web is rewound even when an amount of dirt collected thereby does not reach a predetermined or given level, resulting in unnecessary rewinding of the cleaning web.
On the other hand, when the moving speed of the cleaning target is higher, a shorter time is required for performing a single cleaning operation, so that the cleaning operation is performed a larger number of times within the setting time. As a result, an amount of dirt collected by the cleaning web reaches a predetermined or given level in a shorter time, and the cleaning operation is performed with an unclean portion of the cleaning web until the setting time is elapsed, resulting in a decrease in a cleaning performance.